Many wireless systems operate in a half-duplex communications mode, where wireless devices are either transmitting or receiving, but not using the same temporal and spectral resources. Full-duplex communications modes may double the efficiency of bidirectional communications over the same temporal and spectral resources. In full-duplex mode, a wireless device can transmit radio frequency (RF) signals at a carrier frequency using a transmit antenna while simultaneously receiving RF signals over the same carrier frequency through a collocated receive antenna. A wireless device can also transmit RF signals at a carrier frequency using an antenna while simultaneously receiving RF signals over the same carrier frequency through the same antenna using a circulator or similar device. One limitation impacting full-duplex communications within a transceiver, however, is managing any self-interference signals imposed on the receive antenna by the transmit antenna.
The drawings illustrate only example embodiments and are therefore not to be considered limiting of the scope described herein, as other equally effective embodiments are within the scope and spirit of this disclosure. The elements and features shown in the drawings are not necessarily drawn to scale, emphasis instead being placed upon clearly illustrating the principles of the embodiments. Additionally, certain dimensions may be exaggerated to help visually convey certain principles. In the drawings, similar reference numerals between figures designate like or corresponding, but not necessarily the same, elements.